Term X Definition: The standard abbreviation for exports produced by the foreign sector and purchased by the domestic economy, especially when used in the study of macroeconomics. This abbreviation is most often seen in the aggregate expenditure equation, AE = C + I + G + (X - M), where C, I, G, and (X - M) represent expenditures by the four macroeconomic sectors, household, business, government, and foreign. The United States, for example, sells a lot of the stuff produced within our boundaries to other countries, including wheat, beef, cars, furniture, and, well, almost every variety of product you care to name.